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We study LQ Hya photometry for 1982-2014 with the carrier fit (CF) -methodand compare our results to earlier photometric analysis and recent Dopplerimaging maps. We first utilize different types of statistical methods toestimate various candidates for the carrier period for the CF method. Secondly,a global fit to the whole data set and local fits to shorter segments arecomputed with the period that is found to be the optimal one. The harmonicleast-squares analysis of all the available data reveals a short period closeto 1.6 days as a limiting value for a set of significant frequencies. Weinterpret this as the rotation period of the spots near the equatorial region.In addition, the distribution of the significant periods is found to bebimodal, hinting of a longer-term modulating period, which we set out to studywith a two-harmonic CF model. Weak modulation signal is, indeed retrieved, witha period of roughly 6.9 years. The phase dispersion analysis gives a clearsymmetric minimum for coherence times lower than and around 100 days. Weinterpret this as the mean rotation period of the spots (1.60514 days), andthis value is chosen to be used as the carrier period for the CF analysis. Withthe CF method we seek for any systematic trends in the spot distribution in theglobal time frame, and locally look for abrupt phase changes earlier reportedin rapidly rotating objects. During 2005-2008 the global CF reveals a coherentstructure rotating with a period of 1.6037 days, while during most other timesthe spot distribution appears rather random in phase. The evolution of the spotdistribution of the object is found to be very chaotic, with no clear signs ofan azimuthal dynamo wave that would persist over longer time scales, althoughthe short-lived coherent structures observed occasionally do not rotate withthe same speed as the mean spot distribution.

Multiperiodicity, modulations and flip-flops in variable star light curves III. Carrier fit analysis of LQ Hya photometry for 1982-2014